login
A340092
Carmichael numbers k for which A053575(k) [the odd part of phi] does not divide k-1.
3
1729, 2821, 15841, 29341, 41041, 52633, 63973, 75361, 101101, 115921, 126217, 172081, 188461, 252601, 278545, 294409, 314821, 334153, 340561, 399001, 488881, 512461, 530881, 552721, 656601, 658801, 670033, 748657, 825265, 838201, 852841, 997633, 1024651, 1033669, 1050985, 1082809, 1152271, 1193221, 1461241, 1569457
OFFSET
1,1
MATHEMATICA
odd[n_] := n/2^IntegerExponent[n, 2]; Select[Range[1, 10^6, 2], CompositeQ[#] && Divisible[# - 1, CarmichaelLambda[#]] && !Divisible[# - 1, odd @ EulerPhi[#]] &] (* Amiram Eldar, Dec 31 2020 *)
PROG
(PARI)
A000265(n) = (n>>valuation(n, 2));
A002322(n) = lcm(znstar(n)[2]);
isA340092(n) = ((n>1)&&!isprime(n)&&(!((n-1)%A002322(n)))&&(0<((n-1)%A000265(eulerphi(n)))));
CROSSREFS
Complement of A339869 in A002997.
Subsequence of A340091.
Sequence in context: A154729 A083737 A182208 * A324316 A182207 A138129
KEYWORD
nonn
AUTHOR
Antti Karttunen, Dec 31 2020
STATUS
approved